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Articles 1 - 22 of 22

Full-Text Articles in Physical and Environmental Geography

Water Quality Land Cover Change And Water Quality In Wetlands At The City Of Gresham, Or, Evelyn Barajas, Michael Gonzalez Aug 2023

Water Quality Land Cover Change And Water Quality In Wetlands At The City Of Gresham, Or, Evelyn Barajas, Michael Gonzalez

altREU Projects

The City of Gresham, Oregon has implemented constructed wetlands around the area as an attempt to collect, filter, and purify water from different sources such as rain, agricultural waste, and domestic waste. We focused our research on three different facilities: Columbia Slough Water Quality Facility (CSWQF), Fairview Creek Water Quality Facility, and Brookside Water Quality Facility. For each of these, we conducted tests and looked at the concentration levels for nitrogen and phosphorus nutrients such as NH3-N (ammonium), NO3-N (nitrate), TKN (total Kjeldahl nitrogen), O-PO4 (phosphate), and Total P (total phosphorus), as well as heavy metals like Total Cu (total …


Characterizing Temperature Variability States Across Southern South America And Associated Synoptic-Scale Meteorological Patterns, Judah Adam Detzer Dec 2018

Characterizing Temperature Variability States Across Southern South America And Associated Synoptic-Scale Meteorological Patterns, Judah Adam Detzer

Dissertations and Theses

The aim of this thesis is to understand spatiotemporal temperature variability in southern South America by identifying overarching temperature variability states and their associated synoptic-scale meteorological patterns. Further, the temporal frequency of occurrence of those temperature variability states is investigated as is the role of recurrent low-frequency modes of climate variability (El Niño Southern Oscillation and the Southern Annular Mode) on temperature variability. K-means cluster analysis is used to group all months during the period 1980-2015 into four primary categories for summer and winter separately. Monthly maps of temperature anomalies are provided as input to the k-means algorithm and the …


Sources Of Contaminated Flood Sediments In A Rural–Urban Catchment: Johnson Creek, Oregon, Heejun Chang, Deonie Allen, Jennifer L. Morse, Janardan Mainali Oct 2018

Sources Of Contaminated Flood Sediments In A Rural–Urban Catchment: Johnson Creek, Oregon, Heejun Chang, Deonie Allen, Jennifer L. Morse, Janardan Mainali

Geography Faculty Publications and Presentations

This study investigated the delivery of contaminated sediments to the channel network by urban drainage systems in Johnson Creek in Oregon, USA. Concentrations of five heavy metal concentrations measured in 136 samples collected from 37 stormwater outfalls and 99 bed sampling points were analysed. While concentrations of zinc, cadmium and lead increased with distance downstream in Johnson Creek, this was not the case for chromium and copper. Zinc, copper, and cadmium concentrations in outfalls were significantly higher than those in the stream bed, indicating that stormwater runoff is responsible for delivering contaminated sediments to Johnson Creek. Zinc concentrations in outfalls …


Multiple Methods Of Public Engagement: Disaggregating Socio-Spatial Data For Environmental Planning In Western Washington, Usa, Rebecca J. Mclain, David Banis, Alexa Todd, Lee Cerveny Dec 2017

Multiple Methods Of Public Engagement: Disaggregating Socio-Spatial Data For Environmental Planning In Western Washington, Usa, Rebecca J. Mclain, David Banis, Alexa Todd, Lee Cerveny

Geography Faculty Publications and Presentations

Highlights

• The effectiveness of participatory GIS approaches at engaging different publics was explored.

• Online surveys engaged urbanites; community workshops engaged rural residents.

• Urban and rural residents went to similar places but engaged in different activities.

• Use of multiple data collection methods will broaden public engagement.

• Mapping behavior studies are needed to improve understandings of PPGIS data quality.


Finding Water Scarcity Amid Abundance Using Human–Natural System Models, William K. Jaeger, Adell Amos, Daniel P. Bigelow, Heejun Chang, David R. Conklin, Roy Haggerty, Christian Langpap, Kathleen Moore, Philip Mote, Anne W. Nolin, Andrew J. Plantinga, Cynthia L. Schwartz, Desiree Tullos, David P. Turner Oct 2017

Finding Water Scarcity Amid Abundance Using Human–Natural System Models, William K. Jaeger, Adell Amos, Daniel P. Bigelow, Heejun Chang, David R. Conklin, Roy Haggerty, Christian Langpap, Kathleen Moore, Philip Mote, Anne W. Nolin, Andrew J. Plantinga, Cynthia L. Schwartz, Desiree Tullos, David P. Turner

Geography Faculty Publications and Presentations

Water scarcity afflicts societies worldwide. Anticipating water shortages is vital because of water’s indispensable role in social-ecological systems. But the challenge is daunting due to heterogeneity, feedbacks, and water’s spatial-temporal sequencing throughout such systems. Regional system models with sufficient detail can help address this challenge. In our study, a detailed coupled human–natural system model of one such region identifies how climate change and socioeconomic growth will alter the availability and use of water in coming decades. Results demonstrate how water scarcity varies greatly across small distances and brief time periods, even in basins where water may be relatively abundant overall. …


Quantifying Resilience Of Multiple Ecosystem Services And Biodiversity In A Temperate Forest Landscape, Elena Cantarello, Adrian C. Newton, Phillip A. Martin, Paul M. Evans, Arjan Gosal, Melissa S. Lucash Oct 2017

Quantifying Resilience Of Multiple Ecosystem Services And Biodiversity In A Temperate Forest Landscape, Elena Cantarello, Adrian C. Newton, Phillip A. Martin, Paul M. Evans, Arjan Gosal, Melissa S. Lucash

Geography Faculty Publications and Presentations

Resilience is increasingly being considered as a new paradigm of forest management among scientists, practitioners, and policymakers. However, metrics of resilience to environmental change are lacking. Faced with novel disturbances, forests may be able to sustain existing ecosystem services and biodiversity by exhibiting resilience, or alternatively these attributes may undergo either a linear or nonlinear decline. Here we provide a novel quantitative approach for assessing forest resilience that focuses on three components of resilience, namely resistance, recovery, and net change, using a spatially explicit model of forest dynamics. Under the pulse set scenarios, we explored the resilience of nine ecosystem …


Values Mapping And Counter-Mapping In Contested Landscapes: An Olympic Peninsula (Usa) Case Study, Rebecca J. Mclain, Lee Cerveny, Kelly Biedenweg, David Banis Oct 2017

Values Mapping And Counter-Mapping In Contested Landscapes: An Olympic Peninsula (Usa) Case Study, Rebecca J. Mclain, Lee Cerveny, Kelly Biedenweg, David Banis

Geography Faculty Publications and Presentations

Indigenous peoples, local communities, and other groups can use counter-mapping to make land claims, identify areas of desired access, or convey cultural values that diverge from the dominant paradigm. While sometimes created independently, counter-maps also can be formulated during public participation mapping events sponsored by natural resource planning agencies. Public participation mapping elicits values, uses, and meanings of landscapes from diverse stakeholders, yet individuals and advocacy groups can use the mapping process as an opportunity to make visible strongly held values and viewpoints. We present three cases from the Olympic Peninsula in Washington State to illustrate how stakeholders intentionally used …


Southern Annular Mode Drives Multicentury Wildfire Activity In Southern South America, Andrés Holz, Juan Paritsis, Ignacio A. Mundo, Thomas T. Veblen, Thomas Kitzberger, Grant J. Williamson, Ezequiel Aráoz, Carlos Bustos-Schindler, Mauro E. González, H. Ricardo Grau, Juan M. Quezada Sep 2017

Southern Annular Mode Drives Multicentury Wildfire Activity In Southern South America, Andrés Holz, Juan Paritsis, Ignacio A. Mundo, Thomas T. Veblen, Thomas Kitzberger, Grant J. Williamson, Ezequiel Aráoz, Carlos Bustos-Schindler, Mauro E. González, H. Ricardo Grau, Juan M. Quezada

Geography Faculty Publications and Presentations

The Southern Annular Mode (SAM) is the main driver of climate variability at mid to high latitudes in the Southern Hemisphere, affecting wildfire activity, which in turn pollutes the air and contributes to human health problems and mortality, and potentially provides strong feedback to the climate system through emissions and land cover changes. Here we report the largest Southern Hemisphere network of annually resolved tree ring fire histories, consisting of 1,767 fire-scarred trees from 97 sites (from 22 °S to 54 °S) in southern South America (SAS), to quantify the coupling of SAM and regional wildfire variability using recently created …


The Geography Of Glaciers And Perennial Snowfields In The American West, Andrew G. Fountain, Bryce Glenn, Hassan J. Basagic Aug 2017

The Geography Of Glaciers And Perennial Snowfields In The American West, Andrew G. Fountain, Bryce Glenn, Hassan J. Basagic

Geology Faculty Publications and Presentations

A comprehensive mid-20th century inventory of glaciers and perennial snowfields (G&PS) was compiled for the American West, west of the 100° meridian. The inventory was derived from U.S. Geological Survey 1:24,000 topographic maps based on aerial photographs acquired during 35 years, 1955–1990, of which the first 20 years or more was a cool period with little glacier change. The mapped features were filtered for those greater than 0.01 km2. Results show that 5036 G&PS (672 km2, 14 km3) populate eight states, of which about 1276 (554 km2, 12 km3) are glaciers. …


Evaluating Hourly Rainfall Characteristics Over The U.S. Great Plains In Dynamically Downscaled Climate Model Simulations Using Nasa-Unified Wrf, Huikyo Lee, Duane E. Waliser, Robert Ferraro, Takamichi Iguchi, Christa D. Peters-Lidard, Baijun Tian, Paul C. Loikith, Daniel B. Wright Jan 2017

Evaluating Hourly Rainfall Characteristics Over The U.S. Great Plains In Dynamically Downscaled Climate Model Simulations Using Nasa-Unified Wrf, Huikyo Lee, Duane E. Waliser, Robert Ferraro, Takamichi Iguchi, Christa D. Peters-Lidard, Baijun Tian, Paul C. Loikith, Daniel B. Wright

Geography Faculty Publications and Presentations

Accurate simulation of extreme precipitation events remains a challenge in climate models. This study utilizes hourly precipitation data from ground stations and satellite instruments to evaluate rainfall characteristics simulated by the NASA-Unified Weather Research and Forecasting (NU-WRF) regional climate model at horizontal resolutions of 4, 12, and 24 km over the Great Plains of the United States. We also examined the sensitivity of the simulated precipitation to different spectral nudging approaches and the cumulus parameterizations. The rainfall characteristics in the observations and simulations were defined as an hourly diurnal cycle of precipitation and a joint probability distribution function (JPDF) between …


Aquifer Vulnerability Modeling In New Jersey Through The Use Of Modified Drastic Methodology, Clement Uduk, Tanja Hopmans May 2016

Aquifer Vulnerability Modeling In New Jersey Through The Use Of Modified Drastic Methodology, Clement Uduk, Tanja Hopmans

Student Research Symposium

Due to the global average increase in temperature over the last 50 years, sea levels have been rising and making coastal aquifers more susceptible to saltwater intrusion. The average rate of sea level rise has increased from 2 mm/year to 3.5 mm/year during the twentieth century. The state of New Jersey is not only densely populated but the development along coastlines makes inundation a potential serious threat. New Jersey is diverse in aquifer types, in addition to the types of water bodies surrounding New Jersey, and makes for an interesting case study for groundwater vulnerability. The EPA has a universal …


Short-Tailed Temperature Distributions Over North America And Implications For Future Changes In Extremes, Paul C. Loikith, J. David Neelin Oct 2015

Short-Tailed Temperature Distributions Over North America And Implications For Future Changes In Extremes, Paul C. Loikith, J. David Neelin

Geography Faculty Publications and Presentations

Some regions of North America exhibit nonnormal temperature distributions. Shorter-than-Gaussian warm tails are a special subset of these cases, with potentially meaningful implications for future changes in extreme warm temperatures under anthropogenic global warming. Locations exhibiting shorter-than-Gaussian warm tails would experience a greater increase in extreme warm temperature exceedances than a location with a Gaussian or long warm-side tail under a simple uniform warm shift in the distribution. Here we identify regions exhibiting such behavior over North America and demonstrate the effect of a simple warm shift on changes in extreme warm temperature exceedances. Some locations exceed the 95th percentile …


Impact Of Soil Moisture–Atmosphere Interactions On Surface Temperature Distribution, Alexis Berg, Benjamin R. Lintner, Kirsten L. Findell, Sergey Malyshev, Paul C. Loikith, Pierre Gentine May 2014

Impact Of Soil Moisture–Atmosphere Interactions On Surface Temperature Distribution, Alexis Berg, Benjamin R. Lintner, Kirsten L. Findell, Sergey Malyshev, Paul C. Loikith, Pierre Gentine

Geography Faculty Publications and Presentations

Understanding how different physical processes can shape the probability distribution function (PDF) of surface temperature, in particular the tails of the distribution, is essential for the attribution and projection of future extreme temperature events. In this study, the contribution of soil moisture–atmosphere interactions to surface temperature PDFs is investigated. Soil moisture represents a key variable in the coupling of the land and atmosphere, since it controls the partitioning of available energy between sensible and latent heat flux at the surface. Consequently, soil moisture variability driven by the atmosphere may feed back onto the near-surface climate—in particular, temperature. In this study, …


Near-Surface Internal Melting: A Substantial Mass Loss On Antarctic Dry Valley Glaciers, Matthew J. Hoffman, Andrew G. Fountain, Glen E. Liston Apr 2014

Near-Surface Internal Melting: A Substantial Mass Loss On Antarctic Dry Valley Glaciers, Matthew J. Hoffman, Andrew G. Fountain, Glen E. Liston

Geology Faculty Publications and Presentations

The McMurdo Dry Valleys, southern Victoria Land, East Antarctica, are a polar desert, and melt from glacial ice is the primary source of water to streams, lakes and associated ecosystems. Previous work found that to adequately model glacier ablation and subsurface ice temperatures with a surface energy-balance model required including the transmission of solar radiation into the ice. Here we investigate the contribution of subsurface melt to the mass balance of (and runoff from) Dry Valley glaciers by including a drainage process in the model and applying the model to three glacier sites using 13years of hourly meteorological data. Model …


Getting Salmon Back In Salmon Creek: Systematizing Comparative Water Quality Analysis For Targeted Restoration, Zbigniew J. Grabowski, Sarah Janjua, Michael Swamer, Heejun Chang, Eric Watson Oct 2013

Getting Salmon Back In Salmon Creek: Systematizing Comparative Water Quality Analysis For Targeted Restoration, Zbigniew J. Grabowski, Sarah Janjua, Michael Swamer, Heejun Chang, Eric Watson

Geography Faculty Publications and Presentations

This presentation focuses on water quality restoration efforts in Salmon Creek


Engaging Stakeholders In Ecosystem Service Assessment Under Climate Change And Urban Development Scenarios, Heejun Chang, David E. Ervin, Wes Hoyer, Mike Psaris, Ken Lyons, Emily D. Dietrich, Samantha Hamlin, John Lambrinos, Tammy Winfield, Bobby Cochran Oct 2013

Engaging Stakeholders In Ecosystem Service Assessment Under Climate Change And Urban Development Scenarios, Heejun Chang, David E. Ervin, Wes Hoyer, Mike Psaris, Ken Lyons, Emily D. Dietrich, Samantha Hamlin, John Lambrinos, Tammy Winfield, Bobby Cochran

Geography Faculty Publications and Presentations

This presentation focuses on how scientists can engage stakeholders in ecosystem service assessment.


Examining The Effects Of Climate Change And Urban Development On Water Demand: A Multi-Scale Analysis Of Future Water Demand In Hillsboro, Oregon, Lily Arielle House-Peters May 2010

Examining The Effects Of Climate Change And Urban Development On Water Demand: A Multi-Scale Analysis Of Future Water Demand In Hillsboro, Oregon, Lily Arielle House-Peters

Dissertations and Theses

In the Portland, Oregon, metropolitan area, suburban cities such as Hillsboro are projected to grow as people seek affordable housing near a rapidly growing metropolis. This thesis examines the combined impact of climate change and urban development on both neighborhood and municipal scale residential water demand in Hillsboro, Oregon. I use two models, a surface energy balance model, Local-scale Urban Meteorological Parameterization Scheme (LUMPS), and a system dynamics model, CCDomestic, to investigate changes in residential water demand in the 2040s at two distinct spatial scales, the neighborhood and the municipality. I calibrate and validate each model to the reference period …


Science And Practice Of Integrated River Basin Management : Lessons From North And Central American Unesco-Help Basins, Heejun Chang, Anne Browning-Aiken May 2010

Science And Practice Of Integrated River Basin Management : Lessons From North And Central American Unesco-Help Basins, Heejun Chang, Anne Browning-Aiken

Geography Faculty Publications and Presentations

The Hydrology for the Environment, Life and Policy (HELP) program, a cross-cutting component of the UNESCO International Hydrological Programme (IHP), has as its goal to facilitate dialogue among hydrologists, social and economic scientists, water resource managers, water lawyers, policy experts, and river basin stakeholder communities in setting a research agenda driven by local management and policy issues. HELP seeks to improve the benefits to society by applying the principals of integrated water-resources management to complex, interdisciplinary issues within catchments.

This Monograph is the culmination of a workshop held in 2010 in which the managers from the six North American basins …


The ‘Benchmark Glacier’ Concept – Does It Work? Lessons From The North Cascade Range, Usa, Andrew G. Fountain, Matthew J. Hoffman, Frank Granshaw, Jon L. Riedel Jan 2009

The ‘Benchmark Glacier’ Concept – Does It Work? Lessons From The North Cascade Range, Usa, Andrew G. Fountain, Matthew J. Hoffman, Frank Granshaw, Jon L. Riedel

Geology Faculty Publications and Presentations

Benchmark glaciers were established in many alpine areas during the 1960s as part of the International Hydrological Decade to represent ‘typical’ mass and energy processes on glaciers in different climatic regions around the world. These glaciers have received new interest in the past decade because they are used to infer the contribution of alpine glacier wastage to global sea-level rise. We compare South Cascade Glacier, the benchmark glacier for the northwest contiguous USA, and four other secondary glaciers, against the topographic, area and mass changes of 321 glaciers in the surrounding region. Results show that South Cascade Glacier is unusually …


Quantifying Twentieth Century Glacier Change In The Sierra Nevada, California, Hassan J. Basagic Jan 2008

Quantifying Twentieth Century Glacier Change In The Sierra Nevada, California, Hassan J. Basagic

Dissertations and Theses

Numerous small alpine glaciers occupy the high elevation regions of the central and southern Siena Nevada, California. These glaciers change size in response to variations in climate and are therefore important indicators of climate change. An inventory based on USGS topographic maps (l :24,000) revealed 1719 glaciers and perennial snow and ice features for a total area of 39.l5 ±7.52 km2. The number of 'true' glaciers, versus non-moving ice, is estimated to be 118, covering 15.87 ± 1.69 Km2. All glaciers were located on north to northeast aspects, at elevations >3000 m. Historical photographs, geologic evidence, …


Preliminary Inventory Of Lifeline Systems And Evaluation Of Seismic Hazards In Reno And Sparks, Nevada, Barbara Priest Jan 1981

Preliminary Inventory Of Lifeline Systems And Evaluation Of Seismic Hazards In Reno And Sparks, Nevada, Barbara Priest

Dissertations and Theses

The Reno-Sparks community is in a seismically hazardous area. Recent research indicates that a Richter 7.0 or greater magnitude earthquake could affect the area. Many of the emergency and essential facilities are situated in dangerous geological locations and are housed in outdated structures which could be severely damaged in the event of a major earthquake. Detailed site evaluations need to be made with respect to location of new structures and of existing building safety. The 1979 Unified Building Code seismic provisions should be adopted without exception; Nevada Revised Statute 278 .160 needs to be revised to require a seismic safety …


Spatial Variations In The Intra-Urban Response To A Noise Source, Wilbur David Conder May 1973

Spatial Variations In The Intra-Urban Response To A Noise Source, Wilbur David Conder

Dissertations and Theses

Most research on the urban sonic environment has been recent. One finding has been that physical noise exposure indices calibrate poorly with human noise response. The vagaries of human response to noise have given impetus to research to isolate the factors that differentiate human response to noise. The present thesis continues this research.

The thesis specifies human noise response to occur on three levels: awareness, annoyance, and complaint. The factors that structure each level of noise response are identified in the published Iiterature.

Noise awareness is a function of noise exposure. Noise annoyance is a function of noise exposure to …